1. When using it with Arduino UNO, the only way to get the return message is set it to I2C mode. While using it with Mega or Leonardo, you can use Uart mode.

2. I2C mode:

Cut the connections:

P1 ≯ UART

P2 ≯ RX

P3 ≯ TX

Solder the connections:

P1 -> I2C

P2 -> SCL

P3 -> SDA

3. Make sure PN532 library and Don's NDEF library are downloaded to Arduino library, and use NDEF -> ReadTag

Delete Line 1 to Line 10 ("#else" and the above) to let it start from I2C directly.

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